The assault allegedly took place on a Jetstar flight from Melbourne to Launceston.

A 69-year-old man accused of putting his hands between a woman's thighs while on a plane appeared in the Launceston Magistrates Court on Tuesday.

Charles James Morgan Griffiths, of St Helens, was charged with committing an offence on an aircraft (an act of indecence without consent), after he allegedly assaulted another passenger on a Jetstar flight from Melbourne to Launceston in May last year.

Mr Griffiths did not enter a plea and the matter was adjourned until September 12.